Method and apparatus for drying or calcining



Feb. .16 1926.

J. A. BARR METHOD AND APPARATUS FOR DRYING OR CALCINING I Filed April 9, 1924 INVENTOR. gnu M44! ATTORNEY.

Patented Feb. 16, 1926.

UNITED STA JAMES A. BARE, or MouNTPLEAsAnT, Tmvnnssnn, ssrenon To THE INTERNA- TIONAL AGRICULTURAL CGRPORATION, or NEW YORK, N. Y., A CORPORATION on NEW YGR-K.

METHOD AND APPARATUS FOR DRYING OR GALCINING.

Application filed April 9,

To all whom it may concern.-

Be it known that I, JAMES A, BARR, a citizen of the United States, and resident of Mount Pleasant, in the county of Maury and State of Tennessee,have invented certain new and useful Improvements in Methods and Apparatus for Drying or Calcining, of which the following'is a Specification.

My invention relates to the drying and calcining of materials such as briquets and the like, and will best be understood from the following description taken with the annexed drawing, in which Fig. 1 is an elevational view mainly in vertical section,

showing one illustrative form of my invention; Fig. 2 is fragment of a similar view showing a second illustrative form; and Fi 3 is a detailed View showing the arrangement of the entrance and exit ports for the heating gases.

Referring to Fig. 1, 1O denotes a shaft of any suitable width down through which is fed the material undergoing drying or calcining, or both of these operations, as the case may be, such material being fed to the shaft lO preferably by means of a conveyor 11 and withdrawn therefrom by means of a conveyor 12. It will be apparent that by altering the position of the conveyorwith respect to the end of shaft and by altering the speed thereof, the rate, of travel of the material through the shaft can be regulated. A furnace 13 supplies heating gases which are led through a conduit 14 and are admitted through a plurality of ports 15 to shaft 10 preferably at a point in themiddle portion of the shaft. The gases are abstracted from shaft 10 at exit openings 16 located at points preferably intermediate the entrance openings 15 and the top of the furnace and passing through conduit 17 to the suction or inlet side of the fan 18 and out through the stack 19. The location of ports 15 and 16 and the height of shaft 10 are so chosen with respect to the size of the material, such. briquets, so that the latter will act as seals for both the entrance and exit openings to the shaft 10. The briquets discharged from the furnace are conducted therefrom by means of conveyor 20. From the foregoing it will be seen that the briquets upon reaching the portion of the shaft between the entrance openings 15 an e penings 16 will be su jected to furnace 13.

1924. Serial no. 705,402.

direct contact with the heating gases from By maintaining a suction in the exit conduit 17 some air is drawn into the shaft at the bottom thereof, which has by the compactness of the charge. If de-' sired, a certain amount of secondary combustionimay be produced in the zone of the shaft between the inlet and exit openings 15 and 16, respectively, which will be aided by the heated air passing up from the bottom of the shaft.

Fig- 2 shows a somewhat similar arrangement to that previously described, corresponding parts being designated by the same reference characters, each given an exponent a. In this construction the "furnace gasesare introduced through a plurality of ports 15 extending around the circumference of the shaft 10 and are withdrawn through a conduit which preferably extends from the top of the furnace downwardly to an intermediate point above the openings 15*, and is connected with the suction inlet of fan 18. By means of this construction the sensible heat of the gases leaving the zone of the most intense heating is imparted'to the bri'quets passing down through the upper portion of the shaft 10, while at the same time there is no opportunity for the moisture contained in the gases to deposit upon briquets.

Many changes will suggest themselves to persons skilled in the art without departing from the spirit of my invention.

"1 claim: 7

1. An apparatus for heat-treating material, comprising a shaft having an entrance for material at the top and an exit therefor at the bottom, means for withdrawing said material from the shaft, means for admi ting furnace or other drying gases intermediate the ends of said shaft and suction means for withdrawing all of said gases from contact ith the material un g ing heating at points intermediate the ends of said shaft.

2. An apparatus for heat-treating material, comprising a shaft having an entrance for material at the top and an exit therefor at the bottom, means for withdrawing said material from the shaft, means for admitting furnace or other drying gases intermediate the ends of said shaft and suction means for withdrawing said gases from. contact with the material undergoing heating at points intermediate the ends of said shaft, said means last named permitting entrance of air through the top of said shaft.

8. An apparatus for heat-treating material, comprising a shaft having an entrance for material at the top and an exittherefor at the bottom, means for withdrawing said material from the shaft, means for admitting furnace or other drying gases intermediate the ends of said shaft and suction means for withdra ing said gases from contact with the material undergoing heating at points intermediate the ends of said shaft, said means last named permitting entrance of air through the top of said shaft, and said withdrawing means permitting entrance of air at the bottom of said shaft.

4. An apparatus for heat-treating material, comprising a shaft having an entrance for material at the top and an exit therefor at the bottom, means for withdrawing said material from the shaft, means for admitting furnace or other drying gases intermediate the ends of said shaft, suction means for withdrawing said gases from contact with the material undergoing heating at points intermediate the ends of said shaft, and means for regulating the travel of-material through said shaft.

5. An apparatus for heat-treating material, comprising an open-ended sha-ft, means for feeding material to be heated at the top thereof, means for withdrawing such material at the bottom, said shaft being provided with inlet and exit openings for heating gases intermediate the ends thereof and a fan having its suction end connected withsaid exit openings.

6. An apparatus for heat-treating material, comprising a shaft having an entrance for material at the top and an exit therefor at the bottom, means for withdrawing said material from the shaft, means for admitting furnace or other drying gases intermediate the ends of said shaft and suction means for passing said gases transversely through the material and withdrawing them at a point below the top of the column of material. I

7. An apparatus for heat-treating material, comprising a shaft having an entrance for material at the top and an exit therefor at the bottom, means for withdrawing said material from the shaft, means for admitting furnace or other drying gases intermediate the ends of said shaft and suction means for collecting said gases at a point below the top of the shaft and passing them in thermal contact with the entering material, said means comprising a conduit extending through a portion of the shaft from,

the top downwards and connected with a suction means. 1

8. The method of drying and calcining materials such as briquets, which consists in passing material downwardlythrough a shaft, admitting heating gases at a pointin said shaft, withdrawing said gases at a point above said admission point while permitting air to percolate through said material from either end of the shaft.

9. The method of heat-treating. material which comprises passing the material in a downward direction, passing a heat carrying gaseous medium transversely through said material during a portion of its downward travel and causing downward suction on said material above the place of contact of the gas with the material.

10. The-method of heattreating.materia which comprises passing the material in a downward direction, passingv a heat carrying gaseous medium transversely through said material during a portion of its downward travel and causing suction in opposite directions at the points of entry and exit of said material.

11. The method of heat-treating material which comprises passing the material in a downward direction, passing a heat carrying gaseous medium transversely through said material durin a portion of its downward travel and causing air to pass through said material in opposite directions toward the zone where the hot gaseous medium contacts with the material.

drill ES A. B ARR. 

